Video: Good carbs, bad carbs

Are you one of those people counting carbs to lose weight? The Atkins and South Beach diets have millions of Americans cutting down on bread, and other foods high in carbohydrates. That diet advice has been a little hard to swallow for bread makers. But some nutritionists are saying that not all carbs are diet-killers. Could carbs be ready for a comeback?

By now, we all know that if you want to lose weight, carbohydrates are out and protein is in. Diet after diet tells us to say goodbye to bread, pasta, rice., potatoes, and sugar. Cutting your carbs is suddenly as American as avoiding apple pie.

But for a lot of us, going low-carb is less of a fad and more a new way of life. Americans are dramatically changing their ways of eating. bread sales are down. pasta sales are flat. Fewer people want fries with that, and orange juice -- it's full of sugar and it's not always for breakfast anymore.

So the food business is scrambling to reinvent itself. Low-carb beer? Low-carb fast food? Whatever happened to a brew and a burger? It's enough to make you wonder: Is bread dead?

But Nick Pyle is a man hard at work to make sure that the government's food guide pyramid -- with bread at its base -- remains as unchanged as the capitol dome. Pyle is a lobbyist, but he's not twisting arms for big tobacco or for the carmakers. He lobbies on behalf of bread. Typically, he lobbies on issues like crop subsidies. but that was before Dr. Atkins rewrote America’s menus.

Josh Mankiewicz: “What's going on in this country? Don't people like bread anymore?”

Mankiewicz: “When you go to Capitol Hill and lobby these guys, what do you tell them? Carbohydrates have suddenly gotten this dirty image, and they shouldn't really have it?”

Pyle: “Well, first and foremost, it's time to quit making Americans a victim of the foods they eat. It's time that people recognize the role of personal responsibility in their dietary choices.”

Mankiewicz: “So the new message of the food industry is it isn't our fault, and it isn't our food's fault? Don't blame the bread. Don't blame the pasta. Blame yourself. Don't eat so damn much.”

Pyle: “I would have to agree with you there. I think it's important that people not blame their obesity of being a victim of the foods that they eat.”

But making that argument is only one small part of how carbs are fighting back. last fall, the bread industry held its first ever national summit to address how to fix its image, and keep bread sales from crumbling. the conference was held in november, which was national bread month, thanks to the hard work of guys like Nike Pyle. At the summit, bakers tried to plot the way back to the hearts and stomachs of americans.

Mankiewicz: “Was the bread industry slow in realizing the popularity of low-carb diets and how that was basically going to hit them in the bottom line?”

Barbara Fairchild: “I think what the bread industry needed to do was take a look at the best-seller list. They were all these low-carbohydrate books.”

Barbara Fairchild is editor in chief of Bon Appetit Magazine.

Mankiewicz: “You've been watching how people in this country eat for a long time. If you were advising the carbohydrate industry, what would you tell them?”

Fairchild: “I have to be honest and say that most of the bread in this country that is created for the mass market is really not very good.”

Mankiewicz: “You kind of feel sorry for these people who've been selling squishy white bread all these years.”

Mankiewicz: “Because for so long we wanted it and we were eating it every day.”

Fairchild: “Exactly. I mean it was the squishy white bread patrol. When we went to elementary school and junior high, I mean, that's what we had in our lunch boxes. And now these are the people who really failed to see this revolution coming. It has been a revolution. And they're kind of stuck right now, stuck in the mud, and stuck with a lot of product that they have to figure out what to do with and how to market.”

The next big thing?And there might be another revolution coming. Because just as bread and its starchy cousins are getting an image makeover, a new threat looms on the food horizon.

Mankiewicz: “In the same way there are some good fats and some bad fats, there are good and bad carbohydrates?”

Dr. DavidLudwig: “Yes.“

Dr. David Ludwig of Children's Hospital in Boston is looking at a way of differentiating so-called good carbs from bad by measuring how quickly particular carbohydrates break down into sugar once you eat them. It's called the glycemic index.

Ludwig: “The more rapidly a carbohydrate is turned into sugar, the higher its glycemic index. The refined starchy foods, bread, rice, potato products and most prepared breakfast cereals are rapidly converted into sugar and have a high glycemic index. Fruits, vegetables, nuts and legumes are digested much more slowly.”

Every food is given a number, based on how quickly it turns into sugar and is used up by the body. White bread and potatoes get a high number, whole grains and veggies get a low one. Ludwig found that people who ate a diet full of low index foods, which take longer to digest, stayed full longer and were less hungry.

Mankiewicz: “So if I eat a bowl of Rice Krispies in the morning thinking that it'll stick to my ribs, odds are I'll be hungrier than if I had some fruit.”

Ludwig: “There's fundamentally no difference between a bowl of unsweetened Rice Krispies and a bowl of sugar itself.”

That idea, that starchy carbs raise your blood sugar and make you feel hungry quicker, is a big part of the science behind many of today's popular low-carb diets. But scientists like ludwig say it's not just a diet, but the new way we should look at all food.

But while using a glycemic index would give a passing grade to brown carbohydrates like wheat bread and brown rice, it would still discourage us from eating white bread. And now there's talk of putting the glycemic index right on the package, the way they do in Australia.

Bread lobbyist Nick Pyle is simply appalled.

Pyle: “If you look at the glycemic index, and you're going to base your entire diet on it, you're telling me that jelly beans are better for you than carrots. And I don't think that holds up.”

Mankiewicz: “Can you conceive of a day in the American diet in which we'll be sort of watching the glycemic index and counting that the way people used to count fat grams?”

Fairchild: “Oh, gosh, I hope not. I hope that we don't get to that day. It's sort of dinner table Armageddon I think. Maybe we won't have cell phones any more. We'll just all be sitting at the table with calculators.”

Dateline wires the home of a volunteer, Jenny, from top to bottom with hidden cameras. Then she called repairmen to her house for a simple problem we created as a test with Jenny's pool. NBC's Chris Hansen reports.